Queen forks most often have the enemy king on one prong, but of course two loose enemy pieces also can make fine targets for a double attack. Thus the position to the left is easy if you take the time to ask the right questions. What White pieces are loose? Answer: the bishop at a6 and the rook at h1. Of course you might look for a way to give check while attacking one of them; but don't forget to also ask whether Black’s queen might attack them both at the same time. If the answer isn’t obvious, look for a square where lines leading to both loose pieces intersect, and ask whether the queen can get there. Here Qc6 wins the bishop, since after it is played White only has time to defend the rook.